The present invention is directed to a control system for controlling the operation of electrical devices in a vehicle. The control system includes a power supply, a relay module having a microprocessor, computer memory and at least one output for controlling an electrical device in a vehicle. The relay module is programmable to store configuration data corresponding to predetermined states for the electrical devices to be controlled. The control system includes an input module having a microprocessor and a plurality of variable function switches for selecting predetermined states for the electrical devices. A databus is coupled between the input module and the relay module for transferring communications therebetween. A jumper is provided for configuring the relay module.